Success Rate of Two-Piece Zirconia Implants: A Retrospective Statistical Analysis.

Abstract

About 10 years ago, one-piece zirconia implants were introduced to dentistry. The aim of the study was to evaluate the clinical success of two-piece zirconia implants regarding osseointegration using the manufacturers' warranty data. Over a period of 4 years (2010-2014), the data of warranty replacements of 15,255 sold Zeramex implants were evaluated retrospectively and blinded. Three hundred forty-seven (2.2%) nonosseointegrated implants were sent back. Zeramex T showed an average success rate of 96.7%, whereas Zeralock implants exhibited an average success rate of 98.5%. Furthermore, Zeramex Plus implants exhibit an average success rate of 99.4% within the investigated period. Assuming, that 2% of the failed implants were unreturned, the above-mentioned values show no changes. Assuming 5% (10%) of unreturned nonosseointegrated implants, the average success rate of Zeramex T decreases from 96.7% to 96.6% (96.4%) and of Zeralock from 98.5% to 98.4% (98.4%), respectively. The success rate of Zeramex Plus implants remains unchanged at 99.4%. The results of this study imply that two-piece zirconia implants show competitive success rates, improved from >96.7% to >98.5% over three product generations.